ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  2omotap GIF version

Theorem 2omotap 7625
Description: If there is at most one tight apartness on 2o, excluded middle follows. Based on online discussions by Tom de Jong, Andrew W Swan, and Martin Escardo. (Contributed by Jim Kingdon, 6-Feb-2025.)
Assertion
Ref Expression
2omotap (∃*𝑟 𝑟 TAp 2oEXMID)

Proof of Theorem 2omotap
Dummy variable 𝑥 is distinct from all other variables.
StepHypRef Expression
1 2omotaplemst 7624 . . . . 5 ((∃*𝑟 𝑟 TAp 2o ∧ ¬ ¬ 𝑥 = {∅}) → 𝑥 = {∅})
21ex 115 . . . 4 (∃*𝑟 𝑟 TAp 2o → (¬ ¬ 𝑥 = {∅} → 𝑥 = {∅}))
3 df-stab 843 . . . 4 (STAB 𝑥 = {∅} ↔ (¬ ¬ 𝑥 = {∅} → 𝑥 = {∅}))
42, 3sylibr 134 . . 3 (∃*𝑟 𝑟 TAp 2oSTAB 𝑥 = {∅})
54adantr 276 . 2 ((∃*𝑟 𝑟 TAp 2o𝑥 ⊆ {∅}) → STAB 𝑥 = {∅})
65exmid1stab 4345 1 (∃*𝑟 𝑟 TAp 2oEXMID)
Colors of variables:    wff set class
This proof depends on syntax axioms:  ¬ wn 3  wi 4  STAB wstab 842   = wceq 1402  ∃*wmo 2087  wss 3220  c0 3520  {csn 3709  EXMIDwem 4331  2oc2o 6681   TAp wtap 7614
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4249  ax-nul 4259  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-iinf 4735
This proof depends on definitions:  df-bi 117  df-stab 843  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-ral 2533  df-rex 2534  df-rab 2537  df-v 2823  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-br 4131  df-opab 4193  df-tr 4230  df-exmid 4332  df-iord 4511  df-on 4513  df-suc 4516  df-iom 4738  df-xp 4780  df-1o 6687  df-2o 6688  df-pap 7608  df-tap 7615
This theorem is used by:  exmidmotap  7627
  Copyright terms: Public domain W3C validator